LibNav is a library providing general algorithms for navigation and positioning. It includes datum conversions, reference systems conversions, vector and matrix operations, Least-Mean-Squares, Kalman Filter, Runge-Kutta, statistical tools and more.
TurboGPS is a Java application giving a comprehensive solution for GPS handling. This includes easy editing, sorting and displaying (on a map) waypoints. TurboGPS supports Garmin serial devices and WGS84/RT90 Datum.